recent presentation from AUT with some huge plans for 2009
Forward Plan – Austin Chalk Assets
Program under way to establish a portfolio of appraisal and development
wells.
Need to build up a statistically meaningful population of well performance.
Further wells in the Sugarloaf AMI are planned and permitted.
It is expected that additional rigs will be introduced in 2009 and drilling
expanded into Aurora’s other AMI’s Longhorn and Ipanema, adjacent to
Sugarloaf.
Strategy over next 2 years is to demonstrate productivity over our wide
acreage position, establish reserve potential and build production.
APPRAISAL DRILLING PLANNED TO ROLL IN TO MULTI RIG
DEVELOPMENT PHASE 2009
AUT - Value Proposition
Large net acreage position on giant multi Tcfe resource
8 old well penetrations help delineate field boundaries. 9 recent well
penetrations in Sugarkane field all observing hydrocarbons –including step
out Kowalik #1H
Appraisal & development now – NOT exploration
Near term producer with imminent growth, wells tied in for immediate
production
Premiums paid on recent transactions for analogous US onshore
unconventional gas plays of similar maturity
THE EXISTENCE OF THE FIELD IS ESTABLISHED.
CURRENT PHASE WILL DEMONSTRATE VALUE POTENTIAL.
with AUT claiming the weston well is 100% appraisal and development and ADI reluctant to say anything othert than exploration, the difference of opinion is vast imho.
from adi presentation
• Prospectivity
o Kowalik was a 10km step-out.......(insert your own conclusion here)
Kowalik 50’ flare while drilling Kowalik Initial production
o Gas & condensate saturation confirmed in chalk zone over a
wide area (~60 sq km)
o Gross 600bcfe potential remains
• Forward Plan
o Take a pause in the multi-well drilling program
o Consolidate technical and Chalk Production from Sugarkane wells in
adjoining area
you have kowalik as adi says burning a 50 foot flare during drilling and initial production (clean up) then nothing!! extremely frustrating imho when there is no explanation given.. but there are many factors that have to be considered and tests done primarily to determine what was the cause of the well bore damage in kowalik. then after the initial agreement is made on the potentially correct diagnosis, a solution needs to be agreed upon and initiated.
Formation Damage and Horizontal Wells - A Productivity Killer?
http://www.hycal.com/old/PDFPapers/Formation Damage/Formation Damage & Horiz Wells.pdf
Mechanism of Formation Damage During Drilling of Horizontal Wells
Mechanisms of fonnation damage which may be operative in
reducing the productvity of horizontal wells have been discussed
in the literature by various authors1,2.
These damage mechanisms can be grouped into several major
categories,
Fines Migration.
Fines migration is the motion of naturally preexisting
particulate matter in the pore system. This may be
induced during the drilling process by high fluid leakoff rates of
water or oil-based mud filtrate into the near wellbore region
caused by elevated hydrostatic overbalance pressures or
excessively high underbalanced pressures
External Drilling/Mud Solids Invasion.
The invasion of artificial mud solids (weighting agents, fluid loss agents or
bridging agents), or naturally generated mud solids produced by
bit-rock interactions and not removed by surface solids control
equipment into the fonnation during overbalanced drilling
conditions.
Phase Trapping.
The loss of both water or oil based drilling
mud filtrate to the fonnation in the near wellbore region due to
leakoff during overbalanced drilling operations, or due to
spontaneous imbibition in some situations during underbalanced
drilling operations, can result in permanent entrapment of a
portion or all of the invading fluid resulting in adverse relative
permeability effects which can reduce oil or gas permeability in
the near wellbore region.
Chemical Incompatibility of Invading Fluids with the In-situ
Rock Matrix
Many formations contain potentially reactive
material in-situ in the matrix, including reactive swelling clays
such as smectite or mixed layer clays, or deflocculatable
materials such as kaolinite or other loosely attached fines.
Expansion or motion of these materials within the pore system,
which may be induced by the invasion of non-equilibrium water
based mud filtrates into the near wellbore region, can cause
considerable reductions in permeability
Fluid-Fluid Incompatibility Effects Between Invading Fluids
and In-Situ Fluids.
Oil or water based mud filtrates invading
into the near wellbore region during overbalanced drilling
processes can react adversely with in-situ hydrocarbons or waters
present in the matrix with detrimental results which may reduce
permeability. Problems would include the fonnation of insoluble
precipitates or scales between incompatible waters, de-asphalting
of the in-situ crude or hydrocarbon based drilling fluid caused by
blending of incompatible oils, or the formation of highly viscous
stable water in oil emulsions due to turbulent blending of invaded
filtrates with either in-situ water or oil.
Near Wellbore Wettabllity Alteration and Surface Adsorption
Effects.
Many drilling fluid additives used for mud rheology,
stability, emulsion control, corrosion inhibition, torque reduction
or lubricity contain polar surfactants or compounds which can be
preferentially adsorbed on the surface of the rock. The physical
adsorption of these compounds can cause reductions in
permeability by the physical occlusion of the pore system, in the
case of high molecular weight long chain polymers, particularly
in low permeability porous media where the small pore throats
may be easily bridged by long chain polymer molecules. Polar
compound adsorption may alter the wetting characteristics of the
matrix in the near wellbore region, generally in most cases to a
preferentially more oil-wet state. This causes a potentially
significant increase in water phase relative permeability in this
region, which may adversely elevate producing water oil ratio for
the well if the completion is in a zone where a mobile water
saturation is present.
Mechanical Near Wellbore Damage Effect.
Mechanical action of the bit, combined with tine cuttings, poor hole cleaning and a poorly centralized drill string may result in the formation of a
thin "glaze" of low permeability surrounding the wellbore. This
problem is believed to be aggravated by straight gas drilling
operations, where a large amount of heat is generated at the rockbit
interface due to the poor heat transfer capacity of the gas
based drilling fluid system in comparison to a conventional
drilling fluid. Open hole completions in low permeability clastic formations
tend to be the most probable candidates for this type
of damage. Glazing will not generally occlude large permeability
features, such as fractures or lugs, and the glaze is usually
readily removable in carbonate based formations with a light acid
wash due to its highly soluble nature.
i recommend reading the whole article, it certainly is far superior to being critical of TCEI or the directors of adi.. this is a greenfields play, its very hard to get any data from anyone to help you when your drilling and each time you drill you get new circumstances and events thrown at you, all which change how and what happens in the well bore..
to rescue or fish out a drill string in kowalik would imho have required a different approach to how to keep the well balanced during that phase.. there are lots of ways to speculate on what happened, but imho kowalik was demonstrating a whole different set of numbers and what it produces today is not anything like what it was likely to have produced should the well bore not be damaged for whatever reason.
all imho and dyor